194 Mr. O. Thomas on 
S. (AL) similis, Nels.*, from Cali, Colombia, of which the 
Museum possesses a skull, differs by its unusually slender 
incisors, these being only 1'4 millim. in depth as against 2:0. 
S. chrysurus, Puch.t, the only other allied species, may be 
distinguished by its golden or ferruginous tail. 
Heteromys australis, sp. n. 
A large dark species, with naked soles, allied to /7. melano- 
leucus. 
Fur close and crisp, rather short, spines about 8 millim. 
long by 0°5 millim, broad. General colour dark smoky grey, 
as in the allied species, the hairs of the back finely tipped 
with yellowish, the spines greyish white with black tips. 
Ears short, practically naked, black, finely edged with white. 
A tuft of stiff hairs just in front of the ears black, but in some 
cases white. Muzzle, throat, pouches inside and out, belly, 
and inner sides of limbs white. Lower part of forearms 
indistinctly slaty greyish all round, which colour runs on to 
the median part of the metacarpals, the remainder and the 
digits white. Posteriorly also the metatarsus is indistinctly 
brown, the toes being white. Tail thinly hairy, the rings of 
scales showing through, brown above, white below, the two 
colours not sharply defined. 
Skull stoutly built, broad in proportion to its length ; its 
detailed characters apparently much as in the allied species. 
Dimensions of the type (measured in the flesh) :— 
Head and body 185 millim.; tail 137 ; hind foot, s. u. 30, 
C. .odos Carlos 
Skull: greatest length 35; basilar length 24°53 zygomatic 
breadth 17; length of nasals 14:2 ; interorbital breadth 9:2; 
interparietal 4°7 x 9°5 ; length of palate from henselion 14:2 ; 
diastema 9; length of upper molar series (crowns) 4°5. 
Hab, St. Javier, Lower Cachabi River, N. Ecuador. Alt. 
20 m. 
Type. Female. Original number 64. Collected 23rd 
June, 1900, by G. Flemming and R. Miketta. Fourteen 
specimens examined. 
This is by far the most southern record for the genus 
Heteromys, and is the first discovery of any member of the 
genus to the west of the Andean chain. The species is allied 
to the dark naked-footed species /7. longicaudatus, anomalus, 
melanoleucus, &c., but seems to be different from any of them. 
Among other characteristics its partially dark metapodials 
would alone distinguish it, as the other members of the group 
have these parts wholly white. 
* Bull. Am. Mus. N. H. xii. p. 78 (1899). 
} ‘Revue Zoologique,’ 1845, p. 337. 
